As initial background, reference can be made, for example, to my U.S. Pat. Nos. 6,208,382 and 6,266,093, and to my copending U.S. patent application Ser. Nos. 09/653,983 and 09/954,969, all assigned to the same assignee as the present application.
The 720 60P format for HDTV is almost totally incompatible with the 1080 30I format. However, they both require the same bit rate and produce images with about the same sharpness. The interlaced image suffers from the usual interlace artifacts of interline flicker, line crawl and reduced vertical resolution. Because of the Kell factor in interlaced images, the vertical resolution is not as high as the horizontal resolution. The 720 line format has the disadvantage that a CRT in this format requires a higher horizontal scan frequency. It is one of the objectives hereof to devise a system that combines the advantages of both formats to produce images that are sharper than either one. It is also among the objects hereof to devise improved techniques and apparatus for producing video signals.